Furnace stoker



April 28, 1925. 1,535,961

. A. P s-TRONG FURNACE STOKE-R Filed A ril 17, 1922 2 Sheets-Sheet 1 H ig/@2251. I afimj 5629 1 29 a Aprii 28, 1925.

A. P. STRONG FURNACE STOKER Filed April 17, 192.2 2 Sheets-Shea; 2

, RN ION Patented Apr. 285, 1925.

UNITED STATES 1,535,961 PATENT OFFICE.

ARTHUR I. STRONG, OF CHICAGO, ILLINOIS, ASSIGNOR TO GREEN ENGINEERING COMPANY, OF EAST CHICAGO, INDIANA, ACO'EPOR A'IION 01* ILLINOIS.

FURNACE STOKER.

Application filed April 1?, 1922. Serial No. 554,136.

To all whom it may concern:

Be it known that I, ARTHUR P. STRONG, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Furnace Stokers, of which the following is a specification.

This invention relates to mechanical stokers for furnaces and more particularly to those of the endless chain grate type.

One object of my invention is to provide for the lower lead of the chain grate a supporting floor consisting of a framework of connected longitudinal and transverse metal members with the chambers between to collect droppage through the lower lead and thus present for said lower lead a bearing surface of metal and droppage, to reduce the friction between said parts.

Another object of my invention is to provide air seals for the several draft supplying compartments into which the space between the grate leads is transversely divided by the use of shoes or like members bearing against the grate leads along the upper and lower edges of the members employed to form these compartments so that the latter will not leak into each other along these members when under draft.

A further object of my invention is to provide a floating connection between the lower shoes and the dividing members so that said shoes may be raised upward by droppage carried under them by the lower lead.

A still further object of my invention is to provide air seals for the compartments beneath the lower lead so that air will be prevented from entering the same through the lower lead to affect the draft therein.

Other and further objects of my invention will appear from the following specification taken in connection with the accompanying drawings, in which?- Fig. 1 is a'vertical longitudinal sectional view of a chain grate stoker embodying the features of my invention;

Fig. 2 is an enlarged vertical sectional view through a portion of the construction to show certain details thereof;

Fig. 3 is a perspective view of one of the floating shoes to be hereinafter described;

Fig. -1- is a transverse vertical sectional view taken on line 4l of 1;

Fig. 5 is a horizontal sectional view of a portion of the supporting structure for the lower lead of the chain grate, taken on line 5--5 of Fig. l; and

Fig. 6 is a vertical sectional view taken on line 66 of Fig. 1.

In the drawings, Ihave shown a mechanical stoker of the type having an endless chain grate 1 located in the combustion chamber of a furnace and having upper and lower leads 2 and 3. Said grate 1 extends into the combustion chamber through the front wall of the furnace setting and has its rear or tail end terminating short of the bridge wall 4 to provide a vertical passage through which ash is discharged over the tail end of the grate into a collection chamber (not shown) therebelow, as in furnaces of this general character.

The grate 1 extends horizontally between the side walls 5, 5 of the furnace setting, as shown in Fig. 4, and the space between its upper and lower leads 2, 3, is divided transversely into a plurality of compartments 6, 6 by vertical members 7, 7. These extend the full width of the grate 1' between the upper and lower leads 2, 3 and are secured in any desired manner to the fixed parts at the sides of the grate. The ends of these compartments 6, 6 at one side of the grate, in the particular structure shown in the drawings, are closed by end plates 8, while opposite ends open into communication with conduits 9, as shown in Fig. hfor supplying draft to said compartments.

For supporting the upper and lower grate leads 2, 3, I provide a plurality of skids or rails 10, 11, laterally spaced apart and extending longitudinally of the grate, as shown. The grate leads ride on these skids or rails, and the upper set 10 are for the upper lead 2 while the lower set 11 are for the lower lead 3. The skids 10 extend across the upper edges of the channel members 7, 7, and seat thereon. Between the upper skids 10 are shoes 12 shaped as shown in the drawings and fitting against the underside of the upper lead 2. The shoes 12 are arranged in rows. one row above each member 7, to close the spaces between said members 7 and the upper lead 2 and thus provide air seals between the several compartments 6, 6 along the upper edges of the members 7. Moreover, said shoes 12 have wiping contact with the upper lead .2 so as not to hinder the movement thereof from front to rear of the stoker.

i a pivot 21.

The members 7, 7 terminate short of the lower lead 3, and for closing the spaces between such parts, I provide for each member 7 a plurality of shoes 13, 13 resting on the lower lead and having the general shape shown in the drawings. These shoes 13 also have wiping contact with said lower lead 3 and do not interfere with the movement of that lead during the operation of the grate. The shoes 13 in each row are arranged end to end in substantially abutting relation, as shown in Fig. 1, and each shoe is pivotally connected with its associate member 7 by two plates 14, 14 extending between said shoe and the lower end of said member. As shown in Fig. 3, each shoe 13 has two upright lugs 15, 15 laterally spaced apart and bifurcated to receive cars 16, 16 at the forward edges of the plates 14:. The ears 16 are connected with lugs 15 by pivot pins 17, as clearly shown in Fig. 2.

Secured to the rear side of the members 7 are a plurality of brackets 18, 18, one for each plate let, as shown in Figs. 2 and 4. These brackets 18 project below the members 7 and each has a forwardly projecting lug 19 at its lower end. Each lug 19 is bifurcated to receive an car 20 on the under side of the associated plate 14, as shown. The car 20 is connected with its lug 19 by By the construction described, the shoes 13 may be raised upward by the droppage carried under them by the lower lead 3. The shoes 13 bearing against the lower lead 8 and having endwise abutting relation in each row provide air seals between the various compartments 6, 6 along the lower edges of the members 7, 7, and thus prevent one compartment from leaking into another when under draft through the draft conduits 9.

Arranged beneath the lower lead 3 are a plurality of transverse rows of shoes or members 22, 22, one row beneath each row of shoes 18. The shoes 22 extend between the lower skids or rails 11 and are secured at their ends thereto, as shown in dotted lines in Fig. 6. The shoes 22 have the general shape shown in the drawings and bear against the under side of the lower lead 3. The shoes 22 support the lower lead 3 transversely, while the skids or rails 11 form longitudinal supports therefor. Beneath each row of shoes 22 is an I-beam 23. The shoes 22 rest on these beams and the latter extend transversely of the grate below the lower skids 11 and the latter rest thereon. The ends of these beams are secured to angleplates 24-, 24; secured to vertical plates 25. 25 at the side of the stoker, as shown in Figs. 1, 2 and 1. 7

l'lxtending between the rows of shoes 22 22 for two adjacent compartments 7, 7 shown in Fig. 1 are fiat metal plates 26, 26. These are secured along their front and rear edges to the respective rows of shoes 22, and are supported at their side edges by angle bars 27, 27 secured to the side plates 25, 25 on the inside thereof, as shown in Figs. 1, 2 and 4.

The plates 26 with their connected rows of shoes 22, 22 form chambers 28 beneath the lower lead 3 under two of the compartn'lents 7, '7 and close said compartments from be low to the passage of air into the same through the lower lead 3. The shoes 22 also provide air seals for said compartments along the portions of the lower lead 3 between the lower skids or rails 11.

Droppage falling on the lower lead 3 from the upper lead 2 sifts through the lower lead and collects in said chambers 28, 28 and builds up until it fills the chambers and forms a supporting floor for the lower lead over said. chambers. This collected droppage in conjunction with the skids 11. and shoes 22 forms a composite bearing floor of metal and droppage for the lower lead 3 and results in a reduction of friction in the movement of the chain on said floor. VJhile T have shown and described herein in detail a furnace stoker of my invention, it is of course to be understood that the details of construction and arrangement of pa may be variously changed and modilied without departing from the spirit and scope of my invention.

I claim as my invention:

1. In a furnace stoker, the combination with an endless chain grate having upper and lower leads, of transverse partitions dividing the space between said leads into a plurality of draft compartn'ients, and air sealing means for the compartments along the upper and lower edges of said partitions, the lower sealing means consisting of a row of shoes for each partition and resting on the lower lead, and sealing plates between the shoes and their respective partitions, said plates having pivotal connections with said shoes and partitions.

2. In a furnace stoker, the combination with an endless chain grate having upper and lower leads, of transverse partitions dividing the space between the leads into a plurality of draft compartments, and air sealing means for the con'ipartments extending along the upper and lower edges of said partitions, the'lower sealing means consisting of a row of shoes for each partition and resting upon the lower lead at one side of said partitions, said shoes having upright lugs, brackets secured to said partitions and extending below the same and provided with lugs under said partitions, and scaling plates extending between the shoes and their respective partitions and hinged to the lugs on said slices and brackets, respectively.

In combination in a furnace stoker, an endless chain grate having upper and lower leads, and means beneath the lower lead for supporting the same, said means consisting of connected longitudinal and transverse metal members with chambers between them for the collection of droppage through the lower lead to present a bearing floor for the lower lead of metal and droppage.

4. In combination in a furnace stoker, an endless chain grate having upper and lower leads, and means beneath the lower lead for supporting the same, said means comprising connected longitudinal skids and cross-members and plates between them to provide chambers for the collection of droppage through the lower lead to present to the lower lead a bearing floor of said skids and members and collected droppage between them.

5. A furnace stoker, comprising an endless chain grate having upper and lower leads, vertical members extending transversely across the space between said leads for dividing said space into a plurality of draft supplying compartments, means providing air seals for the compartments along said members by closing the spaces between the grate leads and the upper and lower edges of said members, and means beneath the lower lead for supporting the same and presenting to the lower lead a bearing floor 111 part metal and in part ash.

6. A furnace stoker, comprising an endless chain grate having upper and lower leads, vertical members extending transversely across the space between said leads for dividing said space into a plurality of draft supplying compartments, means providing air seals for the compartments along said members by closing the spaces between the grate leads and the upper edges and lower edges of said members, and means beneath the lower lead for supporting the same and providing a1r seals for sald compartments below said lower lead, said means presenting to the lower lead a bearing floor of metal and droppage sifted through the lower lead.

7. A. furnace stoker, comprising an endless chain grate having upper and lower leads, vertical members extending transversely across the spacebetween said leads for dividing said space into a plurality of draft supplying compartments, means providing air seals for the compartments along said members by closing the spaces between the grate leads and the, upper edges and lower edges of said members, and means beneath the lower lead for supporting the same, said means consisting of connected longitudinal and transverse members with chambers between for the collection of droppage through the lower lead to present thereto a-bearing floor of metal members and droppage.

S. In combination in a furnace stoker, an endless chain grate having upper and lower leads, and means beneath the lower lead for supporting the same, said means comprising connected longitudinal skids and cross members and plates between them to provide chambers for the collection of droppage to present to the lower lead a bearing floor of skids and members and collected droppage, and transverse beams under said skids for supporting the same and said cross-members.

In testimony that I claim the foregoing as my invention, I aflix my signature, this 14th day of April, A. D. 1922.

ARTHUR P. STRONG. 

